Old 30th Apr 2019, 10:58
  #13 (permalink)  
Join Date: Aug 2007
Location: sincity
Posts: 969
Originally Posted by ElZilcho View Post
Is it titled Runaway Stabilizer in the 737? Been a number of years so I honestly can't recall, but in the 777 it's simply titled "Stabilizer" in the QRH. Regardless, the condition statements refer to un-commanded movement of the stabilizer, or "Stabilizer movement without a signal to trim". The MCAS, when it activates, will trim nose down for about 9 seconds to alleviate a sensed high AoA. If a Pilot believes this trim to be in error, the memory items to disconnect the stabilizer would apply. The memory items also apply to a Failed Stabilizer, i.e. if the MCAS puts the Aircraft badly out of Trim and wont allow you to correct it.

As for Stick Shaker, IAS Disagree and TOGA thrust, again this is covered by the Memory items for Unreliable Airspeed. Flaps extended? 10 degrees and 85% N1 if I recall correctly. Easier said than done I realize, as they were battling both stick shaker and overspeed warnings, but those pitch and power settings would have kept them safe... or at the very least gotten them to reduce the thrust from TOGA.

I'm not trying to defend Boeing here, the 737 MAX quite possibly should of never been certified. BUT that's not to say there wasn't a component of Pilot error in the 2 accidents. Lion Air, for example, had an event the day before relating to MCAS but with the help of a jump seat pilot, disconnected the Stabilizer and returned safely.
Its been a while for me too but iirc it's 'runaway stabiliser'.
Just remember the stab running on/off oddly is normalised for 737 crew.

I tend to agree with above, it was TOGA that got them. I imagine it was a good idea when things went pear shaped down low - avoid a stall and get away from the ground. From there it unfortunately kept piling on and was left.

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